In September 2004, a group of students from the Wildlife Institute of India (wii), Dehradun, went to the Sariska Tiger Reserve of Rajasthan for training. Excited about their work, they painstakingly trekked through the hilly 866 square kilometres (sq km) reserve. They couldn't spot a single tiger. Alarmed, they informed A J T Johnsingh, dean, department of animal ecology and conservation biology, wii. The wildlife network galvanised itself and soon the national media was howling out a question: where were the tigers?

The last census the Sariska field directorate conducted was in May 2004. The census revealed 16-18 tigers, plummeting from 25-28 tigers in 2003. "Tigers were last spotted by officials on November 28, 2004,' said Priya Ranjan, deputy conservator of forests, Sariska. Was the vanishing act an annual affair? "No. One or two sightings are common throughout the year,' Ranjan admitted. So what happened this year? The big cats couldn't have been decimated by disease, for no carcasses were found. The Union ministry of environment and forests